Why Getting Your Flu Shot Matters

Health experts across Canada are watching this year’s influenza season closely. A particular strain of the flu virus, H3N2, has changed slightly over the summer. H3N2 strains of influenza have historically been linked to more serious disease, especially among older people. Early signs from countries such as Japan and the United Kingdom suggest their flu seasons started earlier and were more severe than usual. Understandably, many Manitobans are asking an important question: 

If the flu virus has mutated, does the flu vaccine still work?

The short answer is yes. 

The vaccine gives your immune system a head start on fighting three different strains of the flu virus: an H3N2 strain, an H1N1 strain, and a B strain. Each year there are a mix of strains of flu that end up circulating, and we don’t know which strains will circulate more or less until the season is over. This year, both H3N2 and H1N1 strains have been detected in patients in Manitoba and across Canada. Up to now, about half of the strains detected in Canada have been H3N2 strains, and half have been H1N1. And each year, the vaccine ends up being more protective against some strains and less protective against others, just by chance, since the virus changes continually, and the decision about what to put in the vaccine needs to be made well in advance of the flu season. With all that, decades of evaluation have showed that on average the flu vaccine prevents about half of the potential severe outcomes, like pneumonia, hospitalization, ICU admission, and death for those who are immunized.

Why the Flu Vaccine Still Helps, Even When the Match Is Not Perfect

Even if the match is not perfect, the vaccine still helps in two ways:

1. The vaccine helps protect against three types of flu strains, not just one. As noted above, most years, there are a mix of different flu strains that circulate and make people sick. Even if the vaccine is less effective against one strain, it may be more effective against another. And all three strains can make people severely ill, enough to be hospitalized or worse.
2. Less protection against any given strain, doesn’t mean no protection against that strain. Even if the vaccine isn’t a perfect match, it could still provide partial protection. On average, the flu vaccine is about 50% effective at preventing severe disease from the flu. Maybe the level of protection against that strain is only 30% this year. We won’t know until the end of the season. 

Why This Matters for Manitoba’s Health System

Every influenza hospitalization adds pressure to a system that is already stretched. 

Getting your flu shot is not only about protecting yourself. It is also one more way to try to prevent: 

• Surgical wait times from increasing 

• Emergency departments from being overwhelmed 

• Hospital beds from filling up 

A flu vaccine is a simple and effective way to support your community and the health system. 

Common Questions and Concerns

If it is not a perfect match, why get it?

A review of decades of research and evaluation of flu vaccines shows the vaccines work, providing about 50% protection against serious illness, and preventing spread. There are multiple strains that circulate each year, and even if this shot is not a perfect match to one strain, it still likely offers some protection for that strain, plus protection for other strains. 

Isn’t the flu shot weak?

The influenza vaccine is about 50% effective. Because the virus change every year, the vaccine isn’t as good as we have for some diseases that don’t change very much, like measles or polio. But taking the time to get your flu shot is the easiest and most reliable way to reduce your risk in half of something really serious like getting pneumonia or being hospitalized from the flu. 

I’m tired of thinking about vaccines.

Vaccine fatigue is real. After years of COVID-19 messaging, many people feel exhausted. Busy schedules and daily stress can push preventive care to the bottom of the list. 

However, there’s a reason people say an ounce of prevention is worth a pound of cure. Getting vaccinated now can prevent a much more difficult and disruptive experience later. 

I have seen concerning things online about vaccines.

There is more misinformation circulating today than ever before. Decades of research involving hundreds of thousands of people show the following: 

• There is no link between vaccines and autism. 

• There is no evidence that vaccines overwhelm the immune system. 

• Modern vaccines contain fewer antigens than older vaccines. 

When in doubt, speak with a trusted health care provider. They want you to have accurate information so you can make the best choices for your health. 

Where Manitoba Stands Now

Flu is circulating in Manitoba and is on the rise. However, it’s not too late to get your flu shot as there’s a long winter and respiratory season ahead of us. 

The vaccine is free and available across Manitoba. You can also receive your COVID-19 vaccine at the same time, which is important because that virus continues to circulate and evolve. 

Your Flu Shot Protects More Than You Think

Getting vaccinated helps you: 

• Lower your chance of getting really sick 

• Avoid missing work, school, or important family responsibilities 

• Protect loved ones who are elderly, immune-compromised, or medically vulnerable 

• Support Manitoba’s strained health care system 

Even in a year when the virus has changed, the flu shot remains our best tool for reducing serious illness.